Kamala Harris won't save Democrats unless the party unites behind her, says historian who correctly predicted 9 of the last 10 elections

• President Joe Biden withdrew his candidacy, endoring Vice President Kamala Harris.
• Allan Lichtman, who predicted nine out of 10 elections since 1984, said it could be a bad idea.

A professor and historian who successfully predicted the last nine out of 10 elections since 1984 believes Vice President Kamala Harris could secure the presidency if Democrats unite behind her.

Since Biden's poor debate performance against Donald Trump, the president has fielded calls from voters, donors, and congressional colleagues to drop out of the race to make way for a new nominee.

On Sunday, Biden announced that he is withdrawing from the race, endorsing his running mate for the presidency.

Business Insider previously reported that Harris was the most obvious and viable option for Democrats, given the immediate war chest she would get from Biden's campaign and the boost from intraparty support.

But Allan Lichtman, a presidential historian at American University, previously told The Wall Street Journal that based on his prediction model, "Keys to the White House," Harris couldn't save the Democrats. Lichtman's model consists of 13 true-or-false questions to determine the performance of the party holding the White House. If six or more of the 13 keys are false, then the holding party, in this case, the Democrats, will lose.

Lichtman told the Journal that Biden had provided Democrats with seven keys: the incumbency, no significant primary contest, no recession during the election, a strong long-term economy based on real per capita economic growth compared to the average of the previous two terms, major policy changes, no major scandal directly pertaining to the president, and an uncharismatic challenger.

If Harris were to become the new nominee, which is likely but not guaranteed, Democrats risk losing two of those keys Biden secured: the incumbency and the primary contest.

"Biden steps aside, they lose obviously the incumbency," Lichtman told the Journal. "And it's not at all clear that there wouldn't be a big party fight."

Lichtman said at the time that the only scenario in which Harris could maintain the same keys Biden has is if Biden steps down from the presidency now and hands over the White House to the VP a few months before the election.

He said Harris would obtain the incumbency key, and Biden could then release his delegates to his VP to secure the contest key.

But in a social media post following Biden's announcement on Sunday, Lichtman said that Harris may be able to secure the presidency as long as Democrats unite behind her.

"They could still preserve the contest key if the Democrats follow Biden's advice and unite behind Harris," Lichtman said on TikTok, adding that Harris and Biden at least have "an equal chance if they preserve the contest key."

Lichtman has predicted election outcomes since Ronald Reagan secured his second term against Democratic challenger Walter Mondale in 1984. The only election he missed was in 2000 when he predicted Al Gore would secure the presidency. However, the historian argued that he correctly predicted that Gore would win the popular vote.

In 2021, Lichtman told the Miami Herald that he believed Trump would not make a successful political comeback in 2024. He cited some of the former president's flailing businesses, his financial troubles at the time, and the fact that Trump would not be the incumbent.